Descriptive classification of collections such as reading and reference materials, accessible from shelving and other storage facilities involves the widespread use of corresponding synopses, including titles, authors and call numbers on groups of individual cards readily available for thumbing and careful selection of preferred items. Normally each series of cards is arranged in a row resting on one edge and contained in boxes or open-top drawers but, because of what might be called "the domino" effect, they tend to tilt, causing one to lose his place much the same as the way in which the pages of a book flip over when not carefully held or anchored.
Thus, the aggravating problem of attempting to awkwardly copy from a preselected card, while at the same time, keeping the card in full view. Exasperated, the searcher inserts a pencil, a piece of paper or other item, none of which ever seems to be readily available and, usually, without successfully spreading the cards sufficiently or preventing blockage from view of that which is to be copied.